It is known that the sequence {an} is an equal ratio sequence, A2 = 6, A5 = 162, An = 2 * 3 ^ (n-1), if Sn = 242
a5/a2=q^3=27
q=3
a1=a2/q=2
Sn=a1(1-3^n)/(1-3)=2(1-3^n)/(-2)=3^n-1=242
3^n=243
n=5
RELATED INFORMATIONS
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